The major objective of this proposal is to provide animal model systems for the preclinical testing of putative antiviral agents, vaccines or immune modulators directed at the management of herpes simplex virus type 1 (HSV-1), type 2 (HSV-2), cytomegalovirus (CMV), and varicella zoster virus (VZV). A scheme for the evaluation of antivirals where more than one model is offered, and special models that are available for answering specific questions. This scheme offers a rational progression of evaluation from inexpensive screens with few available readouts to more sophisticated models with more diverse endpoints. Complete testing will consist of evaluation in two species for HSV-1 HSV-2 and CMV, thus increasing the reliability of the findings. These models, in general, have proven to be useful for testing antiviral drugs and vaccines and will be used to study combined or sequential therapies.